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RockJock’s Johnny Joint Billet Aluminum RockNut Rear Upper Control Arm Set for the 2021-up Bronco provides you with extremely heavy duty, adjustable length control arms to replace your factory control arms. Adjustable control arms are a must for aligning lifted vehicles to get your pinion angle specs. in check! 
These arms are CNC machined from 7075-T6 aluminum, feature our patent pending RockNut locking nut technology and our 2 1/2 in. Johnny Joints with massive 1 1/4 in. RH/LH threads! 
Johnny Joints, the original and most durable high-articulation urethane suspension joint on the market, feature a smooth steel ball that pivots inside a proprietary urethane shell to provide over 30 degrees (per joint) of quiet, shock dampening articulation - without the excessive deflection found in soft rubber-based flex joints. Johnny Joints deliver a smooth, comfortable on-road ride with the ultimate in off-road capability. They are so trusted, that they are used by multiple commercial suspension companies, for both street and off-road suspension systems. Learn more here.
Arms are fully greasable, fully adjustable and feature machined-in wrench flats. Finished in clear anodize on the arms, black zinc plating on the RockNuts and gold zinc plating on the Johnny Joint ends.


Kit Fits:

  • 2021-up Bronco – All Models


Kit Includes:

  • Johnny Joint Billet Aluminum Rear Upper Control Arms (Pair)


Adjustment Range:

  • Closed – 13.900 in.
  • Extended – 16.000 in.



  • Factory hardware is retained to attach arms to the axle and the chassis.
  • Arms are fabricated from 1 5/8 in. solid 7075-T6 aluminum bar.
  • RockNuts require a 1 3/4 in. wrench
  • Wrench flats on the arms require a 1 1/2 in. wrench.
  • Adjusters feature 1 1/4 in.-12 RH & LH threads.
  • Johnny Joints require non-synthetic, hi-moly lube grease such as our CE-9013G
  • Applicable Johnny Joint Tool for these Control Arms:  CE-9110T


Parts List:

  • RockNut (RH thread):  RJ-572201-1
  • RockNut (LH thread):  RJ-572201-2
  • Johnny Joint Adjuster End Forging (RH thread):  CE-9114F
  • Johnny Joint Adjuster End Forging (LH Thread):  CE-9114F-L
  • Johnny Joint Rebuild Kit:  CE-9110RK
  • Johnny Joint Pivot Ball (frame side):  RJ-348004-1
  • Johnny Joint Pivot Ball (axle side):  RJ-348004-3
  • Zerk Fitting:  CE-1103K21

RJ-182501-101 - 2021-Up Bronco Rear Upper Johnny Joint Control Arms (Aluminum)

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